EF6 IQueryable dynamic linq Where(predicate, values) with DbFunctions.TruncateTime

I have an object with the following attributes in my shortened example:

• Name (string)
• BirthDateTimeStamp (datetime)

I need to be able to construct dynamic queries in the manner shown below.

var predicate = "Name = @0";
var values = new object[]{"Ed"};
myIQueryableDataSource.Where(predicate, values)

This is effective. I want to compare my date and time now.

var predicate = "BirthDateTimeStamp >= @0";
var values = new object[]{someDateTime};

This also works well. But what I really want to do when comparing datetimes—and this problem manifests itself more clearly when using equals—is compare dates alone.

var predicate = "BirthDateTimeStamp.Date >= @0";

Since EF to SQL server does not recognize the Date attribute, this is not feasible.

var predicate = "System.Data.Entity.DbFunctions.TruncateTime(BirthDateTimeStamp) >= @0";

Since I can only access my object's properties in the predicate, this is equally ineffective.

How can I approach this problem in such a manner that the predicate maintains its string format? This code is just a small portion of a much larger parser for my queries that cannot be entirely redone.